1. Field of the Invention
The present invention generally relates to a bicycle hub. More particularly, the present invention relates a bicycle hub with an integrated brake mounting structure for mounting a disc rotor.
2. Background Information
Bicycle wheels are provided with centrally located hubs for rotatably mounting the wheels in the bicycle frame. Conventional hubs comprise a hub axle nonrotatably mounted on the frame, a hub shell disposed around the outside of the hub axle, and a pair of left and right bearings disposed between the hub axle and the hub shell.
Conventionally known examples of such bicycle hubs include those in which a disc rotor of a disc brake device can be mounted on the hub shell. For example, such a bicycle hub is disclosed in Japanese Laid-Open Patent Application No. 2001-246904 (see FIGS. 2 and 6). Thus, some conventional bicycle hubs comprise a rotor attachment unit for fixing the disc rotor in place. A disc rotor typically has an outer ring with a braking surface held between brake pads accommodated by a brake caliper, an inner ring fixed to the rotor attachment unit, and an arm for linking the two rings. Fitting holes connected to the rotor attachment unit are formed at intervals in the circumferential direction of the inner ring. Rotor attachment unit has a plurality protruding portions that are formed at intervals in the circumferential direction on one end of the hub shell. Threaded holes are formed in the protruding portions. The disc rotor is fixed in the rotor attachment unit by screwing bolts into the threaded holes through the fitting holes.
In the conventional configuration, the inner ring provided to the internal periphery of the disc rotor is fixed in the rotor attachment unit. The inner ring is linked to the outer ring by an arm extending from the outer ring that has a braking surface to the internal peripheral side. Thus, when the rotor is fixed to the hub shell at a location a considerable distance away from the braking surface of the disc rotor, the thickness of the disc rotor must be increased to suppress deformation in the disc rotor during braking, making it difficult to lighten the weight of the entire structure. Also, since the diameter of the fixed portion is far smaller than that of the braking surface, there is danger that wobbling will occur in the braking surface and precision will be reduced.
In view of the above, it will be apparent to those skilled in the art from this disclosure that there exists a need for an improved bicycle hub. This invention addresses this need in the art as well as other needs, which will become apparent to those skilled in the art from this disclosure.